摘要
事件相关脑电的量化表征对于研究意识任务识别和认识大脑思维机制具有重要意义。本研究对左右手想象意识任务的脑电信号进行小波包分析,提取出时频域信息熵用来表征事件相关脑电的变化;进而,分析了时频域信息熵特征的事件相关去同步/同步的变化时程,应用互信息评价时频域信息熵对事件相关脑电的表征能力,将相同步理论应用于导联间的脑电信号分析;设计时变线性分类器实现左右手想象运动意识任务识别,获得了满意的结果,最小分类错误率为9%。结果表明,时频域信息熵与频带能量具有一致的变化时程;时频域信息熵具有比频带能量更好的分离性,是事件相关去同步/同步的一个敏感的量化参数;时频域信息熵结合相同步相干性指数,能够提供更多反映大脑意识任务的状态信息。
The quantification of event-related EEG is important in identifying mental tasks and study brain thinking mechanism. In this paper, the parameter of information entropy in time-frequency domain was extracted based on the wavelet package analysis for quantifying the event-related EEG. Then the desynchronization/synchronization （ERD/ ERS） time course was analyzed by information entropy. And the expression capacity of the information entropy to ERD/ERS was evaluated by mutual information. The phase sychronization was also adopted to the EEG analysis. Satisfying results were obtained with the designed time-variable classifier. The error rate was as low as 9% . The results showed that information entropy could effectively describe the ERD/ERS and also display the consistent and similar behaviors with the parameter of the band energy. And information entropy exhibited better capacity to separate the event-related EEG than that of band energy for the classification of hand movements; Information entropy combined with phase coherency index could provide more information on the brain mental tasks involved in the EEG data.
出处
《中国生物医学工程学报》
CAS
CSCD
北大核心
2008年第4期515-520,542,共7页
Chinese Journal of Biomedical Engineering
基金
国家自然科学基金资助项目(30670529
10572056)
甘肃省555人才资助项目
关键词
事件相关脑电
时频域信息熵
相同步
运动想象
event-related EEG
information entropy in time-frequency domain
phase synchronization
motorimaginary
